Description

Rubella is an acute viral disease that can affect susceptible persons of any age. Although rubella is generally a mild rash illness, if contracted in the early months of pregnancy it is associated with a high rate of fetal loss or a constellation of birth defects known as congenital rubella syndrome (CRS) (1).

Occurrence

The last major epidemic of rubella in the United States occurred in 1964 and 1965 when millions of rubella cases led to 20,000 cases of infants born with CRS. Following vaccine licensure in 1969, rubella incidence declined rapidly. Each year from 1992 through 2000, fewer than 500 cases were reported; each year since 2001, fewer than 25 cases have been reported—a 99.8% decline compared with the pre-vaccine era. Although rubella incidence has decreased in all age groups, the decreases have been greatest among children (2). However, since 2001, the incidence among persons younger than 15 years and 15-45 years has been less than 1 per 10,000,000 population in both age groups. From 1997 through 2000, most persons with rubella were born outside the United States. From 2001 through 2004, of the 45 cases with known country of origin, 22 (49%) were among US-born persons (3).

During 1995-2000, an average of five CRS cases was reported annually; since 2001, an average of one CRS case has been reported annually. Since 1997, most women whose infants were reported to have CRS were born outside the United States in countries where routine rubella vaccination programs are not used or have only recently been implemented. From 1998 through 2004, 25 (89%) of 28 infants reported with CRS were Hispanic, and 26 (93%) of 28 were born to foreign-born mothers (3).

In 1998, the United States adopted a goal of elimination of indigenous rubella and CRS by the year 2010. In 2004, an independent panel of internationally recognized experts in public health, infectious diseases, and immunizations reviewed the available data presented and unanimously agreed that rubella is no longer endemic in the United States. With the elimination of endemic chains of rubella transmission in the United States, future patterns of rubella will most likely reflect global disease epidemiology.

Rubella occurs worldwide. Although more than half of all the World Health Organization member countries now use rubella vaccine, rubella still remains a common disease in many parts of the world (4,5).

Risk for Travelers

The risk of exposure to rubella outside the United States can be high; thus, all travelers leaving the United States should be immune to rubella. Acceptable presumptive evidence of immunity to rubella for international travelers includes:

1. documentation of receipt of one or more doses of a rubella-containing vaccine on or after the first birthday, or
2. laboratory evidence of rubella immunity (a positive IgG antibody serologic test).

Birth before 1957 provides only presumptive evidence of rubella immunity and does not guarantee that a person is immune. Therefore, the Advisory Committee on Immunization Practices (ACIP) recommends that birth before 1957 not be accepted as evidence of rubella immunity for women who might become pregnant. A clinical diagnosis of rubella is unreliable and should not be considered in assessing immune status, because many rash illnesses can mimic rubella infection and many rubella infections are unrecognized (6).

Clinical Presentation

Rubella usually presents as a nonspecific maculopapular rash lasting 3 days or fewer (hence the term “3-day measles”) with generalized lymphadenopathy, particularly of the posterior auricular, suboccipital, and posterior cervical lymph nodes. However, asymptomatic infections are common; up to 50% of infections occur without rash. In adults or adolescents, the rash may be preceded by a 1- to 5-day prodrome of low-grade fever, headache, malaise, anorexia, mild conjunctivitis, coryza, sore throat, and lymphadenopathy (1).

Prevention

Although vaccination against rubella is not a requirement for entry into any country (including the United States), persons leaving the United States or living abroad should ensure that they are immune to rubella.

VACCINATION

Rubella vaccine, which contains live, attenuated rubella virus, is available as a single-antigen preparation or combined with live, attenuated measles and mumps vaccines (MMR) (6). Outside the United States, rubella vaccine is available as a single-antigen preparation, or combined with live, attenuated measles or live, attenuated measles and mumps. In the United States, combined MMR vaccine is recommended whenever one or more of the individual components is indicated and is the most common vaccine formulation available (6).

Immunity to rubella is particularly important for health-care providers and women of childbearing age. Health-care providers who treat women of childbearing age should routinely determine their patient’s rubella immune status and vaccinate those who are susceptible and not pregnant. Rubella-susceptible women should be vaccinated who 1) do not report being pregnant, 2) are not likely to become pregnant within 1 month, and 3) have no other contraindicating conditions. Before vaccination, each patient should be counseled to avoid pregnancy for 1 month after vaccination because of the theoretical risk for vaccine virus affecting the fetus. However, routine pregnancy screening is not recommended before rubella vaccination. If a pregnant woman is vaccinated or if she becomes pregnant within 1 month after vaccination, she should be counseled about the theoretical basis of concern for the fetus, but MMR vaccination during pregnancy should not ordinarily be a reason to consider termination of pregnancy (7).

Adverse Reactions, Precautions, Contraindications to Rubella Vaccine

Refer to the Measles (Rubeola) section of this chapter for information on reactions following MMR or MMRV vaccine and for additional precautions and contraindications.

General Vaccine Recommendations, Pediatric and Catch-Up Schedules, and Recommendations for Special Populations

Refer to Chapters 1, 8 and 9.

Treatment

There is no specific antiviral therapy for rubella, and the basic treatment consists of supportive care.

References

1. Plotkin SA, Reef S. Rubella vaccine. In: Plotkin SA, Orenstein WA, eds. Vaccines. 4th ed. Philadelphia, PA: WB Saunders; 2004:707-43.
2. Reef SE, Frey TK, Theall K, Abernathy E, Burnett CL, Icenogle J, et al. The changing epidemiology of rubella in the 1990s: on the verge of elimination and new challenges for control and prevention. JAMA. 2002;287:464-72.
3. Reef SE, Redd S, Abernathy E, Zimmerman L, Icenogle J. The epidemiology of rubella and congenital rubella syn-drome in the United States from 1998-2004: The evidence for absence of endemic transmission. Clin Infect Dis. 2006;43 Suppl 3:S126-32.
4. Reef SE, Cochi SL. The evidence for the elimination of rubella and congenital rubella syndrome in the United States: a public health achievement. Clin Infect Dis. 2006;43 Suppl 3:S123-5.
5. Robertson SE, Featherstone DA, Gacic-Dobo M, Hersh BS. Rubella and congenital rubella syndrome: global update. Rev Panam Salud Pública. 2003;14:306-15.
6. Watson JC, Hadler SC, Dykewicz CA, Reef S, Phillips L. Measles, mumps, and rubella—vaccine use and strategies for elimination of measles, rubella, and congenital rubella syndrome and control of mumps: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 1998;47(RR-8):1-57.
7. Atkinson WL, Pickering LK, Schwartz B, Weniger BG, Iskander JK, Watson JC. General Recommendations on Immunization: Recommendations of the Advisory Committee on Immunization Practices (ACIP) and the American Academy of Family Physicians (AAFP). MMWR Recomm Rep. 2002;51(RR02):1-36.